xref: /openbmc/linux/arch/x86/kernel/stacktrace.c (revision 5bc27dc2f55fd3043597b5a8de6536183f28a449)
1250c2277SThomas Gleixner /*
2250c2277SThomas Gleixner  * Stack trace management functions
3250c2277SThomas Gleixner  *
4250c2277SThomas Gleixner  *  Copyright (C) 2006 Red Hat, Inc., Ingo Molnar <mingo@redhat.com>
5250c2277SThomas Gleixner  */
6250c2277SThomas Gleixner #include <linux/sched.h>
7250c2277SThomas Gleixner #include <linux/stacktrace.h>
8250c2277SThomas Gleixner #include <linux/module.h>
9250c2277SThomas Gleixner #include <asm/stacktrace.h>
10250c2277SThomas Gleixner 
11250c2277SThomas Gleixner static void save_stack_warning(void *data, char *msg)
12250c2277SThomas Gleixner {
13250c2277SThomas Gleixner }
14250c2277SThomas Gleixner 
15250c2277SThomas Gleixner static void
16250c2277SThomas Gleixner save_stack_warning_symbol(void *data, char *msg, unsigned long symbol)
17250c2277SThomas Gleixner {
18250c2277SThomas Gleixner }
19250c2277SThomas Gleixner 
20250c2277SThomas Gleixner static int save_stack_stack(void *data, char *name)
21250c2277SThomas Gleixner {
22250c2277SThomas Gleixner 	return -1;
23250c2277SThomas Gleixner }
24250c2277SThomas Gleixner 
25bc850d6bSArjan van de Ven static void save_stack_address(void *data, unsigned long addr, int reliable)
26250c2277SThomas Gleixner {
27250c2277SThomas Gleixner 	struct stack_trace *trace = (struct stack_trace *)data;
28250c2277SThomas Gleixner 	if (trace->skip > 0) {
29250c2277SThomas Gleixner 		trace->skip--;
30250c2277SThomas Gleixner 		return;
31250c2277SThomas Gleixner 	}
32250c2277SThomas Gleixner 	if (trace->nr_entries < trace->max_entries)
33250c2277SThomas Gleixner 		trace->entries[trace->nr_entries++] = addr;
34250c2277SThomas Gleixner }
35250c2277SThomas Gleixner 
36*5bc27dc2SArjan van de Ven static void
37*5bc27dc2SArjan van de Ven save_stack_address_nosched(void *data, unsigned long addr, int reliable)
389745512cSArjan van de Ven {
399745512cSArjan van de Ven 	struct stack_trace *trace = (struct stack_trace *)data;
409745512cSArjan van de Ven 	if (in_sched_functions(addr))
419745512cSArjan van de Ven 		return;
429745512cSArjan van de Ven 	if (trace->skip > 0) {
439745512cSArjan van de Ven 		trace->skip--;
449745512cSArjan van de Ven 		return;
459745512cSArjan van de Ven 	}
469745512cSArjan van de Ven 	if (trace->nr_entries < trace->max_entries)
479745512cSArjan van de Ven 		trace->entries[trace->nr_entries++] = addr;
489745512cSArjan van de Ven }
499745512cSArjan van de Ven 
509689ba8aSJan Beulich static const struct stacktrace_ops save_stack_ops = {
51250c2277SThomas Gleixner 	.warning = save_stack_warning,
52250c2277SThomas Gleixner 	.warning_symbol = save_stack_warning_symbol,
53250c2277SThomas Gleixner 	.stack = save_stack_stack,
54250c2277SThomas Gleixner 	.address = save_stack_address,
55250c2277SThomas Gleixner };
56250c2277SThomas Gleixner 
579745512cSArjan van de Ven static const struct stacktrace_ops save_stack_ops_nosched = {
589745512cSArjan van de Ven 	.warning = save_stack_warning,
599745512cSArjan van de Ven 	.warning_symbol = save_stack_warning_symbol,
609745512cSArjan van de Ven 	.stack = save_stack_stack,
619745512cSArjan van de Ven 	.address = save_stack_address_nosched,
629745512cSArjan van de Ven };
639745512cSArjan van de Ven 
64250c2277SThomas Gleixner /*
65250c2277SThomas Gleixner  * Save stack-backtrace addresses into a stack_trace buffer.
66250c2277SThomas Gleixner  */
67250c2277SThomas Gleixner void save_stack_trace(struct stack_trace *trace)
68250c2277SThomas Gleixner {
69*5bc27dc2SArjan van de Ven 	dump_trace(current, NULL, NULL, 0, &save_stack_ops, trace);
70250c2277SThomas Gleixner 	if (trace->nr_entries < trace->max_entries)
71250c2277SThomas Gleixner 		trace->entries[trace->nr_entries++] = ULONG_MAX;
72250c2277SThomas Gleixner }
739745512cSArjan van de Ven 
749745512cSArjan van de Ven void save_stack_trace_tsk(struct task_struct *tsk, struct stack_trace *trace)
759745512cSArjan van de Ven {
76*5bc27dc2SArjan van de Ven 	dump_trace(tsk, NULL, NULL, 0, &save_stack_ops_nosched, trace);
779745512cSArjan van de Ven 	if (trace->nr_entries < trace->max_entries)
789745512cSArjan van de Ven 		trace->entries[trace->nr_entries++] = ULONG_MAX;
799745512cSArjan van de Ven }
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